title: Serum vitamin B6, folate, and homocysteine concentrations and oxidative DNA damage in Japanese men and women.
abstract: OBJECTIVE
  Higher vitamin B status has been linked to a lower risk for cancer, but the underlying mechanism remains elusive. The aim of the present study was to examine the association of pyridoxal, folate, and homocysteine (Hcy) with urinary 8-hydroxydeoxyguanosine (8-OHdG), a marker of oxidative DNA damage.
  
  
  METHODS
  The participants were 500 employees (293 men and 207 women), ages 21 to 66 y, of two municipal offices in Japan. Serum pyridoxal and Hcy concentrations were measured using high-performance liquid chromatography (HPLC) method, and serum folate concentrations were measured using chemiluminescent immunoassay. Urinary 8-OHdG concentrations were measured using HPLC method. Multiple regression was used to estimate means of 8-OHdG for each tertile of pyridoxal, folate, and Hcy with adjustment for potential confounders.
  
  
  RESULTS
  In multivariate analysis, 8-OHdG concentration was inversely associated with pyridoxal concentration in men (P for trend = 0.045) but not in women. The association in men was confined to non-smokers (P for trend = 0.033) or those who consumed no or < 20 g/d of ethanol (P for trend = 0.048). 8-OHdG concentrations were not appreciably associated with folate and Hcy concentrations.
  
  
  CONCLUSIONS
  The results suggest that vitamin B6, but not folate and homocysteine, plays a role against oxidative DNA damage in Japanese men.
authors.affiliation: Department of Epidemiology and Prevention, Clinical Research Center, National Center for Global Health and Medicine, Tokyo, Japan. kuwahara@ri.ncgm.go.jp
authors.forename: Keisuke
authors.initials: K
authors.lastname: Kuwahara
authors.forename: Akiko
authors.initials: A
authors.lastname: Nanri
authors.forename: Ngoc Minh
authors.initials: NM
authors.lastname: Pham
authors.forename: Kayo
authors.initials: K
authors.lastname: Kurotani
authors.forename: Ayami
authors.initials: A
authors.lastname: Kume
authors.forename: Masao
authors.initials: M
authors.lastname: Sato
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Kawai
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kasai
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Mizoue
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000328:Adult; D000368:Aged; D044466:Asian People; D015415:Biomarkers / Q000097:blood / Q000652:urine; D002851:Chromatography, High Pressure Liquid; D003430:Cross-Sectional Studies; D004249:DNA Damage / Q000187:drug effects*; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000652:urine; D005260:Female; D005492:Folic Acid / Q000097:blood*; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D007564:Japan; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D018384:Oxidative Stress / Q000187:drug effects*; D011730:Pyridoxal / Q000097:blood; D025101:Vitamin B 6 / Q000097:blood*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D006710:Homocysteine; D011730:Pyridoxal; D025101:Vitamin B 6; D000080242:8-Hydroxy-2'-Deoxyguanosine; D005492:Folic Acid; D003849:Deoxyguanosine
keywords: Cross-sectional study; Oxidative DNA damage; Serum folate; Serum homocysteine; Serum vitamin B(6); Urinary 8-OHdG